I often get this question from entrepreneurs or my students in entrepreneurship at Kristiania University.
The answer is that no one really knows - in advance! The only way to know if your idea has any potential is to execute on it, to give it a try.
Ideas themselves are not worth much. Everyone can think of business ideas, but very few are able to execute on them and last long enough to see the potential of their ideas turn into actual businesses. That's one of the reasons why it is pointless (in the vast majority of cases) to try to keep your idea secret.
Plus, the idea you have today will most likely not be what you end up with. If you actually decide to execute on it, you will discover along the way what is the right and wrong thing to do or build, who are your clients, how much would they pay or not for your product/service, and so on...
So the only way to know is to test your idea and validate it in REAL LIFE. By doing that, you should be able to figure out if there is a need in the market relatively quickly.
You can start by talking to your potential clients, ask about their needs, the problems they face, the solutions they are currently using to tackle these problems and so on. You will learn a lot in the process.
I see way too many entrepreneurs who stay at the idea stage, fearing engaging with potential clients or not knowing what to do with their ideas.
If that is how you feel... Send me a message at firstname.lastname@example.org, I can give you some guidance to get you started.
Raja Skogland, CEO at MyTheia.com